Finally having some time to revisit this, but not completely working.
The following needs to be run in the Docker VM (I’m using Ubuntu, haven’t moved to CoreOS yet):
apt-get install nmap
Then run this command in Dom0 of XCP-ng host:
xscontainer-prepare-vm -v UUID -u DOCKERUSER
Xen and XCP-ng Center see the Docker integration now, but won’t list the Containers.
References:
http://richsitblog.com/index.php/2016/08/14/coreos-on-citrix-xenserver-7-setup-guide/
https://discussions.citrix.com/topic/393075-xenserver-not-showing-containers-in-xencenter/